1. Field of the Invention
This invention pertains generally to paint ball guns used for recreational and training purposes. For the purposes of this disclosure, paint ball guns are specifically defined as apparatus that propel capsules filled with paint from a barrel in rapid succession and at relatively high speeds. The paint ball capsules are designed to break upon impact with an object or person, thereby rendering an identifiable mark without injuring the person or object.
2. Description of the Prior Art
Paint ball guns employ a compressed gas as the propellant to fire a paint-filled projectile called a "paint ball" or a pellet. The paint balls are of spherical shape having a fragile outer shell, and are designed to break on its target and thus deliver its paint to the target surface. Most paint ball guns are of single shot or semi-automatic design, but are capable of firing in rapid succession a relatively large number of paint balls in a short period of time. However, it is desirable to be able to control the firing to single shots, bursts of a predetermined number of shots, and full automatic, namely continuous firing as quickly as the gun is capable of with a single depression of the trigger.
Mechanisms have earlier been disclosed for converting a semi-automatic gun to fully automatic. A problem though, with fully automatic or rapid semi-automatic firing is that the gun fires too fast. Firing too fast is painful to the victim who gets hit with a multitude of paint pellets rather than just one or two. Firing too fast also wastes ammunition and, in the case of CO.sub.2 activated guns, cools down the gun, causing slower gas expansion, which causes a low pellet velocity. Lower velocity means shorter effective gun range and accuracy. Also, a slower moving paint pellet will bounce off an opponent rather than breaking and marking the opponent. The cooled gun also may not give enough velocity to the recoiling bolt for the bolt to latch, causing repeated uncontrolled firing of the gun (cycling) even when the trigger is released. As the rate of firing increases, there is increased incidence of "chopping" or rupture of the paint balls, as will be discussed further hereinafter.
Paint ball guns generally comprise a reciprocating pneumatic bolt confined within a bolt housing coupled to a rifle barrel by means of a receiver. A magazine for supplying paint balls is coupled to the junction of the bolt housing and barrel at the receiver. In operation, a gas such as air, CO.sub.2 or N.sub.2 at a pressure substantially above atmospheric pressure drives the bolt forwardly. The impact of the bolt and the pressure of the gas propel the paint ball through the barrel. The flow of high pressure gas to the bolt is generally regulated by a mechanically controlled pneumatic system.
Paint ball magazines are little more than hoppers positioned atop the gun with a feed tube descending to communication with the receiver. The paint pellets are simply poured into the hopper, which typically holds from 60 to 200 pellets, and is easily reloaded by pouring in more pellets as needed. The pellets fall by gravity sequentially into the receiver forwardly of the bolt. Guns and attachments have now been designed to help this gravity feed by using gas expansion to push the new pellet into the chamber quicker than gravity alone. These feeding improvements still are not fast enough or exacting enough to reliably keep up with a typical full auto rate of fire or a "double pull" wherein the trigger is manually pulled faster than a successive ball can be properly seated. Attempting to shoot a semi-automatic gun at extremely fast rates will cause the gun to fire before the pellet has completely entered the firing chamber, causing the pellet to jam or burst inside the gun. Additionally, the slight jerking of a semi auto gun while rapidly pulling the trigger causes a distinct loss of aiming accuracy.
U.S. Pat. No. 5,791,325 to Anderson concerns a paint ball gun having a positive feed mechanism associated with a hopper-type magazine to minimize jamming of the gun.
U.S. Pat. No. 4,770,153 to Edelman discloses a pneumatic weapon having a series of built-in valves and regulators whereby the electronic pulses produce single, burst or continuous fire.
U.S. Pat. No. 5,727,538 to Ellis concerns an air gun that is loaded and fired electronically. The chopping of paint balls is minimized through the use of sensors which detect the location of the paint balls and position of the bolt within the receiver mechanism. A selector switch permits full automatic, three-round burst, or semi-automatic firing.
U.S. Pat. No. 5,413,083 to Jones describes an attachment for a paint ball gun which adapts the gun to fire in automatic, semi-automatic and other patterns of fire. Said attachment has a mechanical mechanism for manipulating a protrusion of the gun, such as a bolt handle, a programmable pulse generator for determining the pattern of fire, and an electromechanical device for converting the signals generated by the pulse generator into a mechanical motion for driving the mechanical mechanism which manipulate the bolt handle.
Although the aforesaid patents address the issues of minimizing ball chopping, and providing selectable firing patterns, they generally require factory-specialized construction at the time of manufacture of the gun. The Jones attachment, although useful as an add-on or after-market feature, is bulky, and is suitable only for guns having a particular bolt configuration.
It is accordingly an object of the present invention to provide a system for controlling the firing pattern of a paint ball gun.
It is a further object of this invention to provide a control system as in the foregoing object which can be installed onto an existing paint ball gun.
It is another object of the present invention to provide a control system of the aforesaid nature of compact size and interactive with the trigger of the gun.
It is a still further object of this invention to provide a control system of the aforesaid nature which will minimize the chopping of paint balls.
It is yet another object of the present invention to provide a system of the aforesaid nature of simple, durable construction amenable to low cost manufacture.
These objects and other objects and advantages of the invention will be apparent from the following description.